Article sorting apparatus



1961 R. E. CHESTNUTT ETAL 2,998,135

ARTICLE SORTING APPARATUS Filed March 29, 1956 2 Sheets-Sheet 1 INVENTORSI ROBERT E. OHES TT, KEITH C. COR 3 BYWMM THEIR A ORNE g- 1961 R. E. CHESTNIJTT ETAL 2,998,135

ARTICLE SORTING APPARATUS Filed March 29, 1956 2 Sheets-Sheet 2 INVENTORS! ROBERT E.CHESTNUTT,

KEITH c. CORMIA,

2,998,135 ARTICLE SORTING APPARATUS Robert E. Chestnutt, Rexford, and Keith C. Corinna, Scotia, N.Y., assignors to General Electric Company, a corporation of New York Filed Mar. 29,1956, Ser. No. 574,730 2 Claims. (Cl. 209-120) Our invention relates to article sorting means and pertains more particularly to new and improved apparatus for sorting wafer-like articles such as the mica insulators generally included in receiving tube mount structures.

Manufacturers using wafer-like articles generally receive same in bulk and varying in thickness. For example, electronic tube manufacturers generally receive wafer-like mica insulators from vendors or suppliers in bulk quantities and ranging in thickness from approximately .002 inch to .015 inch, with the majority of such insulators being about .008 inch thick. It has been found from experience that micas under a .006 inch thickness are not generally satisfactory for assembly into quality-type receiving tubes and, therefore, when the micas are received in bulk in varying thicknesses, it is necessary to separate the undesirably thin micas from those which meet the requirements of the user. Additionally, following separation of the micas it is desirable that they be sorted or delivered to certain different places according as they are rejected or accepted for use in receiving tube production.

A primary object of the present invention is to provide new and improved apparatus for sorting articles.

Another object of the present invention is to provide new and improved apparatus for sorting wafer-like articles in accordance with the thicknesses thereof.

Another object of the present invention is to provide new and improved article sorting apparatus adapted for a substantially high degree of discrimination and reliability in operation. ,Another object of the present invention is to provide new and improved article sorting means adapted for selective predetermination of the sorting operations effected thereby.

Another object of the present invention is to provide new and improved apparatus adapted for sorting waferlike articles without damaging same. Further objects and advantages of our invention will become apparent as the following description proceeds and the features of novelty which characterize our invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

In carrying out the objects of our invention we provide apparatus including means for providing an upward flow of fluid which is substantially uniform in crosssection. Our apparatus further includes means for holding a supply of unsorted wafer-like articles and means for picking articles out of the supply and delivering them seriatim transversely through the flow of fluid so as to present the maximum effective cross-section of each article to the fluid flow. In accordance with differences in weight, different articles are differently influenced by the fluid and thus caused to be delivered into different receptacles and sorted.

For a better understanding of our invention, reference may be had to the accompanying drawing in which:

FIGURE 1 is an enlarged fragmentary and partially broken away perspective view illustrating article sorting apparatus constructed in accordance with a preferred embodiment of our invention;

FIGURE 2 is a schematic illustration of the operation of the rotary valve in the apparatus of FIGURE "1;

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FIGURE 3 is an enlarged fragmentary sectional view illustrating the feature of the apparatus of FIGURE 1 whereby the seriatim delivery of individual articles to the conveying means is insured;

FIGURE 4 is an enlarged fragmentary perspective illustration of a modified form of arrangement for insuring the seriatim delivery of individual articles to the conveying means; and

FIGURE 5 is a fragmentary and partially brokenaway elevational view of a modified form of apparatus constructed in accordance with the present invention.

For purposes of illustration the present invention has been shown in the drawing as incorporated in apparatus adapted for sorting mica insulators or disks of the type generally used in receiving tube mount structures. In the drawing the mica insulators are designated 1 and are illustrated as including a plurality of diametrically arranged apertures 2 which are generally formed in such devices for receiving the ends of electrodes or electrode support elements thereby to maintain the electrodes in spaced relation between a pair of micas 1. It is to be understood from the outset, however, that while our invention is shown in apparatus for sorting mica disks or wafer-like articles, it is not limited in application to such purpose; but, as will be seen hereinafter, is equally applicable to the sorting of articles of various types.

As also clear from the drawing, the present invention is being illustrated in apparatus adapted for sorting micas into merely rejected and accepted groups. It is further to be understood from the outset that the present invention is not limited in application to the sorting of elements into two groups or categories but is adaptable for sorting the articles into several groups according to varying ranges of thickness or weight.

The apparatus illustrated in FIGURE 1 of the drawing includes a support structure having a base plate 3 and a pair of side supports 4 whereby the base plate 3' is supported at an angle of approximately 15 to the horizontal, the purpose of which will be seen herein after. Secured substantially centrally on the base plate 3 is a standard 5. Journalled in the standard 5 is a drive shaft 6. The drive shaft 6 is adapted for being driven counterclockwise in FIGURE 1 by means of a drive motor 7 through a reduction gear arrangement 8 and a suitable belt and pulley arrangement generally designated 9. The drive shaft 6 extends through the standard 5 in which it is journalled and through the hub. 10 of a rotary valve generally designated 11. The hub 10 is suitably secured to the standard 5 and thus is adapted1 for constituting the stationary member of the rotary va ve.

Provided in the hub 10 is a first peripherally opening manifold port 12 to which is connected a manifold line 1'3 which, in turn, is connected to a vacuum source 14. The manifold line 13 preferably includes means (not shown) for enabling flexing thereof which is generally desirable to avoid damage from vibratory motions, etc. Also included in the hub 10 is a second peripherally opening manifold port 15 to which is connected a manifold line 16 which, in turn, is connected to an air pressure source '17. The line 16 may also include means enabling flexing thereof. The particular construction and operation of the just-mentioned ports 12 and 15 will be described in greater detail hereinafter.

Cooperating with the hub 10 is a cylinder 18 adapted for constituting the movable portion of the rotary valve. The cylinder 18 is formed with a plurality of circumferentially spaced ports 19 extending radially therethrough and is suitably secured coaxially to the drive shaft 6. Similarly secured to the end of the cylinder 18 is the end of a shallow drum or closed-end annular mem- Patented Aug. 29, 1961 her generally designated 20. The side walls'of' the drum 20 constitute a rim 21 wherein is formed a plurality of spacedtaped bores 22 corresponding in number and circumferential disposition to the ports 19 in the cylinder 18. Suitably fitted in the bores 22, as by threading are cylindrical axially'bored plugs or inserts 22a. The plugs 22a are so positionable in the bores 22 as to cooperate therewith in providing shallow seats or recesses 23 which are just slightly larger in, diameter than the mica insulators. Additionally, the axial bores in the plugs 22a constitute ports 22b and provided for connecting each of these ports with the corresponding one of the ports 19 in the cylinder 18 is a tube or line 24. The plugs'22a are adjustably positionable in the bores 22 for predeter minedly varying the depth of the seats 23 and the lines 24 include telescoping or otherwise yieldable coupling structures 25 to enable adjustable positioning of the plugs;

In the arrangement described to this point, and as seen in FIGURE 2, the manifold port 12 in the stationary hub of the'rotary valve 11 extends arcuately from a position approximately 20 to the left of bottom center of the hub clockwise to a position approximately beyond top center. Thus, any port 19 in the cylinder 1% disposed intermediate these positions is connected through the line 13 to the vacuum source 14 whereby the corresponding line 24 connects the corresponding port 22b in the inner periphery of the drum with the vacuum source. In this manner disks I placed in the bottom of the drum 'will be attracted to the ports 22b in the walls of the drum, and thus become positioned in the seats 23 and carried therein around the drum.

The manifold port 15 in the hub 10 is shorter than the port 12 and extends only from a point about 18 beyond top center to a point about 35 beyond top center; Thus, when any port 19 in the cylinder 13 is disposed between these twolast-mentioned positions the corresponding ports 2212 on the rim of the drum 20 is out of communication with the vacuum source and is brought into communication with the compressed air source 17 through the corresponding line 24 and the manifold line 16. In this manner disks being carried around by the drum arepositively blown or ejected by air pressure downwardly for apurpose-which will be seen hereinafter.

Provided for feeding the micadisks' or insulators 1 into the bottom portion of the drum 20 in order that the disks may be attracted to the ports 22b is a hopper 26.- The hopper 26 comprises a semi-cylindrical element With the lower edge thereof conforming and in close juxtaposition to the inner edge of the rim 21 of thedrum. The hopper, like all of the elements on the base. plate 3', is inclined about 15 to the horizontal. Thus, a supply of unsorted disks 1 in the hopper 26 is caused to slide downwardly into the lower portion of the drum and, against theclosed end thereof whereby, due to the rotation of the drum, and the vacuum, disks are attracted to the ports 22b. and caused to become seated in the disk seats 23 on the inner. surface of the rim of the drum 20. In this. manner individual disks are picked out of the supply thereof and carried around with the drum to the above-described ejection position. In order to improved this pickup operation there is provided a compressed air line 27 which may be connected to the compressed air source 17 and extendsinto the hopper 26 on. the lower side thereof. Thus, a jet of air is directed through the lower portion of the hopper and against the. end of the drum which effectively agitates the micas for. improving the pickup thereof.

The just-described pickup. operation, operates most satisfactorily and any tendency toward damage to the individual micas is minimized when there is not too great an accumulation of micas in the lowermost portion of the drum. Thus, the apparatus is normally operated with a substantially small amount of micas in the hopper 26 and automatic means is provided for slowly replenishing the supply'or slowly'metering-small amounts-of micas into the hopper. This last-mentioned means comprises a substantially wide conveyor belt 28 carried on a spaced pair of rollers 36 journalled. between a pair of support arms 31 which are suitably supportedin a position above the hopper 26. One of the rollers 30 is connected axially to a drive shaft 32 which, in turn, is adapted for being driven by a slow-speed motor 33 through a high-reduction gear arrangement 34. This arrangement provides for an extremely slow movement of they upper portion of the conveyor belt 28 toward the drum 20. Thus, when a supply of mica; insulators 1 is spread on the upper surface of the belt 28 in the manner shown in FIGURE 1, they are caused to be moved or dropped very slowly or metered slowly into the hopper 26; Provided for avoiding movement of the insulators 1 oh? the side portions of the conveyor belt 28 is a pair of side boards 35 suitably secured to the upper edges of the support arms 31.

Provided on the inner face of the drum 2% is a pair of radially disposed elongated elements 36. These elements prevent excess micas tending to ride up the rim of the drum from rolling down the side walls, and thus. disturbing the pickup process, by intercepting such excess micas and carrying them up to a point Where they are caused to roll therealong down to the center of. the drumand fall at random to the bottom of the drum.

Additionally, the mica insulators 1, as pointed out above, generally include apertures 2. As seen in FIG- URE 3, it is sometimes the case during operation of the apparatus that, because of the apertures 2. in a mica positioned in one of the seats 23, a second mica is caused to be attracted to the rim of the drum by the vacuum holding the first mica. Such second micas are excess and undesirable since they would tend to disturb any seriatim delivery of micas to the upper positions of the drum. Accordingly, we have provided means for removing excess micas and thus insuring the seriatim movement of micas to the upper positions of the drum. As seen in FIGURES l and 3, this means may comprise a rotating element which may be a brush 40. The brush 40 may be mounted on a shaft 41 adapted for being driven by a motor 42 suitably mounted on the hopper 26. By means of the motor 42 the brush 40 is rotated counter to the movement of the drum 20 and positioned so close to the inner surface of the rim 21 of the drum as to wipe therefrom any excess micas in the manner illustrated in FIGURE 3, which excess micas fall back into the supply thereof in the bottom of the drum.

Alternatively, and as seen in FIGURE 4, the excess micas may be removed from the vacuum pickup ports 22b by means of a suitably nozzled air jet provided through the agency of a line 43 suitably mounted on the side of the hopper 28 in a suitable manner and connected to the compressed air source 17. In this arrangement the end of the line 43 is adapted for directing the air jet just over the inner surface of the rim 21 whereby the jet is effective for removing from the walls of the drum 20' any micas in excess of the ones seated in the pickup ports 22b as these ports move past the jet;

After the micas are carried on the vacuum ports to the position just past top center corresponding to manifold port 15, compressed air supplied to the ports 22b through the manifold port 15 is efiective for blowing or ejecting the micas from the port downwardly. Provided for intercepting such, ejected micas is a take-0E chute. 47 or article directing means. The chute 47 receives and conducts the micas in a. flat-wise position onto a conveyor belt 48. The conveyor belt 48 is mounted between a pair of spaced drums 49 journalled in a vertical frame member 50, secured to and extending from the base plate 3. One of the drums 49 is driven by a constant speed motor 51 through a suitable speed reduction arrangement 52 mounted on a horizontal plate secured to one of the supports 4. Thus, the conveyor belt 48 is driven at a uniform velocity which, in turn, provides uniform velocity of movement of the micas 1 regardless of the weight or thickness thereof. The belt 48 directs the micas 1 in the flat-wise positions along a predetermined course which extends transverse the gravitational forces of the earth, which predetermined course is horizontal in the presently described structure.

Supported by the plate 50 and disposed at the end of the belt 48, whereat it is disposed in the mentioned predetermined course, is a wide-mouthed nozzle 53. The

nozzle 53 includes spaced inserts 53a whereby it is adapted for directing an upward laminar flow of fluid which is substantially uniform in cross-section to the underside of each mica in the course of travel of the micas.

Now, the mica disks 1 are substantially identical in planar configuration and specific gravity. They difier in weight, however, in accordance with thickness. Thus, it will be seen that a sorting of the disks as to their thicknesses may be obtained by sorting them in accordance with their correlated weights. This is accomplished by the above-described arrangement including the nozzle 53 in the manner now to be described in detail.

The nozzle '53 is connected by a line 54 to a suitable compressed air source which may be the source 17. Provided in the line 54 is a control valve 55 whereby the pressure of the flow of air from the nozzle may be selectively and predeterminedly adjusted and preset.

Ln accordance with the setting of the valve 55 the force of the air emitted from the nozzle 53 will be suflicient for substantially supporting micas of a certain weight or less and insufiicient for supporting heavier micas. Thus, when the micas move off the end of the belt and are no longer supported by the belt in the predetermined course of travel, the maximum cross-sectional area of each mica is presented to the air from the nozzle which is subsequently effective for supporting certain of the lighter micas in the mentioned course of travel for permitting such micas to continue therealong in the manner indicated by the arrows designated 56. These micas are received in a chute 57 whereby they are directed into a receptacle 58. The micas received in the receptacle 58 will, in accordance with the selected predetermined setting of the valve 55, be of a predetermined thickness or less, and when it is the purpose to cull out micas of unsatisfactory thinness the receptacle 58 will receive and hold the rejects."

Micas which are satisfactory as to thickness will be heavier than the mentioned certain micas, and these heavier micas will be substantially unsupported by the air flow from the nozzle 53. Therefore, such heavier micas will not continue along the predetermined course 56 but will be diverted from or drop out of the course and follow the arrows 59 into a chute 60 whereby they will be directed into a receptacle 61 adapted for receiving and holding micas which are of accepted thicknesses. Thus, the micas 1 which were unsorted when placed on the conveyor belt 28 for feeding into the drum 20 are sorted according as they are rejected or accepted from the standpoint of thickness.

Viewed from another standpoint the course of mica travel indicated by the arrows 59 might be considered the predetermined course of travel along which the heavier or acceptable micas are permitted to travel while the lighter micas are deflected or diverted by the air flow to the course 56 for conduction to the receptacle 58 for rejects.

It will be understood that while our invention is illustrated in equipment for sorting articles into only two categories of thickness or weight, it is possible to utilize our invention in sorting articles into several categories of varying thicknesses or weights merely by substituting several appropriately dimensioned chute members for the two chute members 57 and 60.

It will be seen further that our drum 20 could be constructed to provide any plurality of rows of ports 22b and each row could be provided with a corresponding take-off chute 47 and associated sorting means. It will be seen still further that in some applications it may be desirable to pick up more than one article on each port 22b. This can be accomplished by adjusting the positions of the plugs 22a to increase the depth of the seats 23 and thus vary the capacity thereof.

Additionally, it will be seen that instead of utilizing an air nozzle at the end of the conveyor belt 48, the belt could be suitably perforated for having a fluid flow directed upwardly therethrough. In this type of structure the fluid flow could be utilized for raisig micas of predetermined dilferent light weights predetermined distances off the surface of the belt and thus causing them to be directed into suitable receptacles thereby to effect sorting thereof. The heavier micas would remain on the belt and be carried to another receptacle.

Illustrated in FIGURE 5 is a modified form of the present construction. In this embodiment the drum 20 and the mica feeding arrangement is identical to that described above with regard to the structure of FIGURE 1. However, in the structure of FIGURE 5 the micas are dropped from the drum -20 fiat-wise into an inclined takeoff chute 62 which includes an aperture 63 in an intermediate portion thereof and adjacent the lower end thereof. Provided for cooperating with the chute at the aperture 63 to provide a flow of air transverse the course of travel or to the undersides of micas sliding fiat-wise down the chute is an air nozzle preferably corresponding in width to the width of the aperture '63 and similar in structure and function to the nozzle 53. The nozzle 64 is connected by a line 65 to the compressed air source 17. Provided in the line 65 is an adjustable valve 66 adapted for controlling the pressure of the air flow emanating from the nozzle 64. Thus, the flow may be controlled for supporting micas of predetermined light weight in the aperture 63 and permitting them to travel over the aperture and continue down the chute in the predetermined course determined by the chute in a manner indicated by the arrows 67. Here also, if desired, the heavier micas which fall through the aperture might be considered to be the ones which continue along a predetermined course while the micas which continue down the chute might be considered to be the diverted ones.

The micas which continue down the chute are received in a receptacle 68 adapted for receiving rejected micas. The heavier and accepted micas will be unsupported by the air flow in the aperture 63 and will, therefore, fall through the aperture 63 and be diverted from the course and conducted by a direction controlling element 69 into an appropriate receptacle 70 adapted for receiving micas of acceptable thickness.

It will be seen that the chute can include a plurality of successive apertures and nozzle arrangements and the pressure of fluid flowing from each nozzle could be predeterminedly controlled so that micas may be sorted according to a substantial number of different thickness ranges.

While we have shown and described specific embodiments of our invention, we do not desire our invention to be limited to the particular forms shown and described, and we intend by the appended claims to cover all modifications within the spirit and scope of our invention.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. Apparatus for sorting wafer-shaped articles com prising a rotatable drum including a cylindrical peripheral wall provided with a plurality of circumferentially arranged equally spaced vacuum chucks, each of said chucks having an article receiving recess dimensioned to accommodate only a single article, a hopper for holding a supply of unsorted articles and having a discharge end disposed to discharge articles therefrom into the path of rotation of said chucks, valve means associated with said rotatable drum for extinguishing the vacuum to each of said chucks and ejecting conveying means disposed in the path of articles ejected irom said chucks and arranged to transport said articles along a predetermined course in successive equally spaced relation with each of said articles resting on its nonperipheral surface, a nozzle at the discharge end of said conveying means arranged to direct a stream of air upwardly substantially normally against the underside of articles discharged from said conveying means whereby to provide articles discharging from said conveying means with trajectories difiering according to the weight of the respective articles, and a plurality of collectors arranged in the paths of said diifering trajectories to recover selectively articles of different respective Weights.

- 2. Apparatus for sorting wafer-shaped articles comprising a drumrotatable about a substantially horizontal axis and including a radially extending wall and a cylindrical peripheral wall, said peripheral wall having on its interior surface a plurality of circumferentially equally spaced vacuum chucks, each of said chuck-s having an article receiving recess dimensioned to accommodate only a single article, a hopper for holding a supply of unsorted articles and having a discharge end disposed to discharge articles therefrom into the path of rotation of said chucks, a wiper mounted adjacent the path of said chucks and arranged to dislodge therefrom articles retained thereby other than articles accommodated in said recesses, radially extending bafiles on the radially extending wall of said drum, valve means associated with said rotatable drum for extinguishing the vacuum to each of said chucks and ejecting an article carried thereby at a predetermined point in the path of rotation of said chucks, conveying means disposed in the path of articles ejected from said chucks and arranged to transport said articles along a predetermined course in successive equally spaced relation with each of said articles resting on one of its non-peripheral surfaces, a nozzle at the discharge end of said conveying means arranged to direct a substantially laminar stream of air upwardly substantially normally against the underside of articles discharged from said conveying means whereby to provide articles discharging from said conveying means with trajectories differing according to the weight of the respective articles, and a plurality of collectors arranged in the paths of said differing trajectories to recover selectively articles of different respective weights.

References Cited in the file of this patent UNITED STATES PATENTS Germany Apr. 8, 1954 

